Aeronautical structures utilize this type of panel in a wing or ventral beam box section, for example. These panels, highly loaded in compression, are generally sized for stability in terms of compression if holed and damage tolerance.
Damage tolerance is a particular penalty for this type of panel with low damage tolerance in the event of impacts on their edge. Indeed, their superposed carbon fiber ply structure open on the edge is greatly weakened by an impact on that edge. The shock of the impact in fact induces “decohesion” (i.e. separation) of the plies through the exercise of out-of-plane forces.
The precise field of the invention is therefore protecting the edges of self-stiffened panels.
In order to alleviate this fragility and this lack of damage tolerance, the panels are protected by rigidly fastened edge-cover structures. One edge-cover of this type is known from the patent document FR 2 902 689 or FR 2 869 871, for example.
Such edge-covers have a limited efficacy because they have a U-shaped overall structure that does not allow good absorption of impact energy. This energy is in fact transmitted to the structure or to the panel, the shape having no really damping character. This transmission may result in damage to the panel and its connections to other parts.
Moreover, these edge-covers, entirely stuck to the stiffener, are not demountable. To remove them, the assembly must be destroyed, which leads to the destruction of the protection itself. The structure to be protected is therefore not easy to inspect after an impact.